The empress leilia is a medium sized member of the emperor butterfly family (Nymphalidae). They are found in the desert washes, thorn scrubs, and canyons of the southwestern United States and Mexico. Like many other members of the emperor family they are typically not found on flowers. They prefer to eat tree sap and dung only occasionally eating flower nectar. Males are often found perched on their larval host plant, spiny (desert) hackberry waiting for females.